// -*- Mode: C++; tab-width: 4 -*-
// $Id$
//
// A simple interface to win32 Timers
//
// Author: Sam Rushing <rushing@nightmare.com>
//

// @doc - Contains autoduck comments for documentation

#include "pywintypes.h"
//#include "abstract.h"

static PyObject *timer_id_callback_map = NULL;

VOID CALLBACK
py_win32_timer_callback (HWND hwnd, UINT msg, UINT_PTR timer_id, DWORD time)
{
	CEnterLeavePython _celp;
	PyObject * py_timer_id = PyWinLong_FromVoidPtr((void *)timer_id);
	if (!py_timer_id){
		PyErr_Print();
		return;
		}
	// is this timer id recognized?
	PyObject * callback_function = PyDict_GetItem (timer_id_callback_map, py_timer_id);
	if (!callback_function){
		::KillTimer (NULL, timer_id);
		PyErr_Warn(PyExc_RuntimeWarning, "Unrecognized timer id");
		Py_DECREF(py_timer_id);
		return;
		}
	// call the user's function
	// create a 'death grip' on the callback function, just incase
	// the callback itself removes the function from the map.
	Py_INCREF(callback_function);
	PyObject * callback_args = Py_BuildValue ("(Ok)", py_timer_id, time);
	PyObject * result = PyEval_CallObject (callback_function, callback_args);

	if (!result) {
		// Is this necessary, or will python already have flagged
		// an exception?  Can we even catch exceptions here?
		PyErr_Print();
		}

	// everything's ok, return
	Py_DECREF(callback_function);
	Py_XDECREF(callback_args);
	Py_XDECREF(result);
	Py_DECREF (py_timer_id);
	return;
}

// @pymethod int|timer|set_timer|Creates a timer that executes a callback function
// @rdesc Returns the id of the timer, which can be passed to kill_timer to stop it.
// @comm Uses the SetTimer function.
static PyObject * 
py_timer_set_timer (PyObject * self, PyObject * args)
{
	PyObject *callback;
	PyObject * py_timer_id;
	UINT elapse;
	UINT_PTR timer_id;

	if (!PyArg_ParseTuple (args, "kO:set_timer",
		&elapse,		// @pyparm int|Elapse||Timer period, in milliseconds
		&callback))		// @pyparm function|TimerFunc||Callback function.  Will be called with with 2 int args: (timer_id, time)
		return NULL;
	// make sure the callback is a valid callable object
	if (!PyCallable_Check (callback)) {
		PyErr_SetString (PyExc_TypeError, "argument must be a callable object");
		return NULL;
		}

	// create the win32 timer
	Py_BEGIN_ALLOW_THREADS;
	timer_id = ::SetTimer (NULL, 0, elapse, py_win32_timer_callback);
	Py_END_ALLOW_THREADS;

	if (!timer_id)
		return PyWin_SetAPIError("SetTimer");
	py_timer_id = PyWinLong_FromVoidPtr((void *)timer_id);
	if (!py_timer_id){
		::KillTimer (NULL, timer_id);
		return NULL;
		}

	// associate the timer id with the given callback function
	if (PyDict_SetItem (timer_id_callback_map,
						py_timer_id,
						callback) == -1) {
		::KillTimer (NULL, timer_id);
		Py_DECREF(py_timer_id);
		return NULL;
		}
	// everything went ok.
	return py_timer_id;
}

// @pymethod boolean|timer|kill_timer|Creates a timer that executes a callback function
// @comm Uses the KillTimer API function.
static PyObject *
py_timer_kill_timer (PyObject * self, PyObject * args)
{
	PyObject * py_timer_id;
	UINT_PTR timer_id;
	if (!PyArg_ParseTuple (args, "O:kill_timer",
		&py_timer_id))	// @pyparm int|IDEvent||Timer id as returned by <om timer.set_timer>
		return NULL;
	if (!PyWinLong_AsVoidPtr(py_timer_id, (void **)&timer_id))
		return NULL;
	if (timer_id_callback_map)
		if (0 != PyDict_DelItem (timer_id_callback_map, py_timer_id))
			return NULL;

	BOOL rc;
	Py_BEGIN_ALLOW_THREADS;
	rc = ::KillTimer (NULL, timer_id);
	Py_END_ALLOW_THREADS;
	return PyBool_FromLong(rc);
}

#ifdef _DEBUG
static PyObject *
py_timer_timer_map (PyObject * self, PyObject * args)
{
	if (!PyArg_ParseTuple (args, ""))
		return NULL;
 
	Py_INCREF (timer_id_callback_map);
	return (timer_id_callback_map);
}
#endif

// List of functions exported by this module
// @module timer|Extension that wraps Win32 Timer functions
static struct PyMethodDef timer_functions[] = {
	// @pymeth set_timer|Creates a timer that executes a callback function
	{"set_timer",		py_timer_set_timer,		METH_VARARGS, "int = set_timer(milliseconds, callback}\nCreates a timer that executes a callback function"},
	// @pymeth kill_timer|Stops a timer
	{"kill_timer",	py_timer_kill_timer,	METH_VARARGS, "boolean = kill_timer(timer_id)\nStops a timer"},
#ifdef _DEBUG
	{"_id_timer_map",	py_timer_timer_map,		1},
#endif
	{NULL,			NULL}
};


PYWIN_MODULE_INIT_FUNC(timer)
{
	PYWIN_MODULE_INIT_PREPARE(timer, timer_functions,
				  "Extension that wraps Win32 Timer functions");

	timer_id_callback_map = PyDict_New();
	if (!timer_id_callback_map)
		PYWIN_MODULE_INIT_RETURN_ERROR

	if (PyDict_SetItemString(dict, "error", PyWinExc_ApiError) == -1)
		PYWIN_MODULE_INIT_RETURN_ERROR;
	if (PyDict_SetItemString(dict, "__version__", PyString_FromString("0.2")) == -1)
		PYWIN_MODULE_INIT_RETURN_ERROR;

	PYWIN_MODULE_INIT_RETURN_SUCCESS;
}
